Tree stand



FIG. 1 is a perspective view of the tree stand showing the new design;

FIG. 2 is a front elevation view;

FIG. 3 is a rear elevation view;

FIG. 4 is a left side elevation view;

FIG. 5 is a right side elevation view;

FIG. 6 is a top plan view; and,

FIG. 7 is a bottom plan view. 

The ornamental design for a tree stand, as shown and described. 